I've had a bag of Kingsford blue bag charcoal in my garage for about two years. I'm out of what I regularly use so I opened up the bag and saw all the charcoal is covered with a gray mold or something. This happened with another bag of Kingsford I had years ago that I had stored for awhile in my garage. Is the charcoal still OK to use. I used that other bag and to my knowledge no one got sick.